Experimental approach to improving early postirradiation restoration in the hemopoietic system of irradiated canines.

Experiments on mongrel canines exposed to total body irradiation in free-in-air dose of 3.85 (LD 95/45) or 4.05 Gy were carried out to evaluate the therapeutic effectiveness of some of bone marrow immediate-after-irradiation extraction, incubation in the presence of protein synthesis inhibitor and reimplantation in the organism (the reimplantation method) or bone marrow extraction alone (the extraction method). There were tested various kinds of methods that differed in bone marrow-blood mix volume extracted, in large or in small volumes. It has been determined that the reimplantation method in large volumes and the extraction method in small volumes are equally effective. Being supplemented with supportive therapy by antibiotics during d8-d24, the methods allowed the rescue at 4.05 Gy irradiation significantly more animals than in the case of therapy alone or its combination with ineffective variants of the methods. The positive effect of the methods manifested in a higher level of leukocyte nadir on d17, earlier reaching 0.5 x 10(9) and 1 x 10(9) leukocytes per liter, and increasing 45 days survival. The mechanism of positive influence of the methods on the radiation injury of hemopoesis seems to be related to increased cytokine producing because of the irritation of bone marrow stromal cells and thus favorable interference in the early restoration processes.